Beckhoff KL2602 Series, Документация

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Commissioning
KL2602, KL2622, KL2634 30 Version: 2.4.0
For the -0010 variants applies:
The relays internally of these terminals would be switched near to the zero voltage crossing of an AC supply.
Hereby the lifetime of the outputs is no longer dependent by the absolute lifetime of the relay. The result of
an exemplary long term test with the following boundary conditions represent that:
• Each channel of a terminal EL2622-0010 (or KL2622-0010 respectively) switches cyclic one time per
second a beforehand complete discharged capacitive load of approximately 40 µF (without any
additional resistor in series) to 230 V AC, whereof a permanent current of approx. 4 A is resulting.
• After abortion of the test over more than 200,000 switching cycles per channel the expected lifetime of
the terminal outputs are above them of the relays.
• Under the same test conditions but without connection of the neutral wire that disables the operation of
the zero voltage detection, the relay was out of order after less than 10 switching cycles.
Economic life-time
It is the maximum values that are to be expected that are critical to selection of the right terminal
rather than the technical figures for normal operation!
4.2 Notes on contact-protecting switching of the
EL26x2-0010/ KL26x2-0010 terminals
In order to minimize starting currents in the form of capacitive loads in electronic ballasts, it is possible to
switch on loads at the time when the mains voltage zero crossing occurs. To this end this Bus Terminal
features continuous zero crossing detection for frequencies between 45 Hz and 65 Hz.
At 50 Hz this results in an additional switch on delay to the usual relay delay of 10 ms, at 60 Hz the value is
approx. 8.33 ms.
Operation only possible at the same phase
No different phases may be applied at terminal points 2 and 6 (400 V voltage between the terminal
points is not permitted!).
General notes on commissioning
• In order to be able to use this function, an alternating voltage for internal detection must be present
between terminal points 2 and 3. The feeding in of an alternating voltage can be done via the blade
contacts, too.
• Under usual grid conditions the terminal switches near the voltage zero crossing with a typical temporal
accuracy of <1 ms.
• If no zero crossings of an alternating voltage occur for a prolonged period, the system responds directly
to the switch on or switch off request by the PLC, without delay.
• For the EL versions, it is advisable for the PLC to wait until the status becomes “1”, indicating
successful synchronization of the terminal with the zero crossings of the prevailing alternating voltage.
The status bit can be linked via the process data of the terminal and evaluated by the PLC.
• If the “detection” voltage between terminal points 2 and 3 is switched off in the meantime, the Bus
Terminal is only able to maintain the synchronization for a very short time. Thereafter, it indicates the
loss of synchronization by switching off the corresponding status LED or the status bit. A new
synchronization process commences once the supply voltage is restored. Subsequently the switching
operations of the relay once again take place near the voltage zero crossing.
Missing synchronization
If a relay is switched on without synchronization, a current-minimized switch on operation near the
alternating voltage zero crossing cannot be guaranteed.